Integrated transcriptomics and metabolomics uncover metabolites and pathways in American bullfrog (Aquarana catesbeiana) response to Elizabethkingia miricola infection

Abstract

Elizabethkingia miricola is a widespread zoonotic bacterium capable of causing diseases in both humans and animals. A comprehensive understanding of the host response mechanisms to E. miricola infection is critical for the development of effective control strategies. In this study, American bullfrogs (Aquarana catesbeiana) were experimentally infected with E. miricola, and transcriptomic and metabolomic changes in the liver and spleen were analyzed at 0, 1, 2, and 3 days post-infection. A total of 3818 and 4166 differentially expressed genes (DEGs) were identified in the liver and spleen, respectively, along with 518 and 464 differentially abundant metabolites (DAMs). Short time-series expression miner (STEM) analysis revealed six and seven significant gene expression patterns in the liver and spleen, respectively, with alterations in numerous immune and lipid metabolism pathways identified by gene set enrichment analysis (GSEA). The metabolomic data showed dysregulation of 86 pathways in the liver and 75 in the spleen, predominantly involved in lipid, amino acid, and carbohydrate metabolism. Additionally, the IL-17 signaling pathway and glycerophospholipid pathway were highlighted as pivotal immune and antibacterial defense pathways in bullfrogs through KEGG enrichment and STEM analysis. Notably, the multi-omics study uncovered a complex regulatory network and highlighted stage-specific immune and metabolic responses in bullfrogs during E. miricola infection, providing valuable insights into their defense mechanisms.